This might be a dumb question but since Gamzee never actually went God tier, how do we know what the bard costume looks like? Do we ever see Cronus wear it? I suppose what I'm asking is; is the cod piece an actual part of the costume in canon?

We did see Cronus in his God Tier outfit in Ministrife, but Ministrife also taught us that you can change what the outfit looks like so not all Bards need the cod piece, it’s just part of the default ensemble